To-scale check of bumpers, underbody, roof and width on a garage slope.
Tap or drag on the chart to move the car.
List the pieces from the street to the garage floor. Each piece needs a length and one of: rise, angle or grade. A negative value means the garage is lower than the street.
The margin covers suspension dip, passengers and luggage. The header height is measured from the ground at the door; leave it empty to skip the roof check.
Mirrors pass over low curbs, so only the body width counts there. Walls catch mirrors.
Crossing at an angle stretches each transition, so the car sees a gentler change, but it needs more width. The model follows the car’s centreline; in reality the wheels on each side reach the slope at slightly different times.
Changes on this tab apply straight away.
The front bumper catches in dips, where the ramp gets steeper (approach angle). The underbody catches on crests, where it flattens out again (breakover angle). The rear bumper catches where the ramp levels out behind the car (departure angle). How sharply the slope changes matters more than the average slope.
Split the ramp wherever the slope changes. For each piece, measure the length with a tape and the angle with a phone level app, or the rise with a straight edge and a spirit level. Short easing pieces at the top and bottom make a big difference, so include them.
Green clears with more than your safety margin, amber clears with less, red touches. A tight result is worth a real check: measure your own bumpers and underbody, and allow for passengers and luggage.